


Red Blueberries

by sansislife12 (orphan_account)



Category: Undertale (Video Game)
Genre: Alternate Universe - Underfell, Alternate Universe - Underswap, Cherryberry - Freeform, Dom Sans, Dom/sub, Ecto-Penis (Undertale), Ecto-Tongue (Undertale), Ecto-Vagina (Undertale), Ectobiology, Lust at First Sight, M/M, Sanscest - Freeform, Skeleheat, Smut, Sub Sans, Underfell Papyrus, Underfell Sans, Underswap Sans, heat - Freeform
Language: English
Status: Completed
Published: 2016-07-14
Updated: 2016-07-14
Packaged: 2018-07-24 00:47:04
Rating: Mature
Warnings: No Archive Warnings Apply
Chapters: 3
Words: 2,260
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/7486782
Author URL: https://archiveofourown.org/users/orphan_account/pseuds/sansislife12
Summary: <blockquote class="userstuff">
              <p>Underswap! Sans and Underfell! Sans are a couple now. Blue is experiencing his ninth heat and that makes Red so "happy..."</p>
            </blockquote>





	1. The Beginning Of Something Entirely Else

"What did you want me here for?" Underfell! Sans asked as he walked into the bright blue room.

"I'm over here, silly," a voice said.

Red turned around to shut the door. He turned back around. "Where?"

"Here..." the voice sang throughout the room. A soft blue light was dancing across Red's vision as something pounced on him from the side.

"Shit! Don't do that to me, Blue!"

He backed up a bit. "I-I'm sorry," the little blue Sans stammered. "Are you okay now?"

"I'm okay, but why am I here again? If Boss finds that I'm missing he'll literally have my skull on a silver platter. Literally!"

"Well, I just can't stand being here without you, Red. I'm so lonely... and lustful..." He started to unzip Red's jacket.

"Whoa, whoa, whoa, whoa. Chill out for a second there, B—mph!" Blue pounced on him, entangling them both into a French kiss. Their tongues colliding with each other, not missing a single place to explore.

The red-eyed skeleton pulled back panting. "What's gotten into you?" he asked as he noticed blue magic spilling from the other's eye socket.

" _You!_ " He kissed him again, a blue glow forming between his legs.

Red knew exactly what was happening then.

It was that time of the year again.

Blue was in skeleheat.

"Wait," Fell said right as Swap was about to kiss him again. "You're in skeleheat, aren't you?" A smile slid across his face.

"That's right, Red. And for that you get a special treat..." The smaller skeleton smiled and went over to the bed. Reaching under it, he pulled out a collar with a chain attached to it.

"Blue..." Red started to say something but was marvelled by what he pulled out next. It was a long, black leather belt.

"Yes?" Blue responded as he motioned the slightly taller skeleton to come over to him.

Red abided and was instantly pinned onto the bed. Arms above his head and hands crossed over each other, Blue began to tie them to together and to the bed post bars.

"Jeez, Blue, I didn't know you had it in ya to do such a thing." A smirk widened into a smile.

Underswap tightened the belt, causing a small moan from Underfell. "You like that, don't you?" There was no response so he put the collar around the other's neck and tugged on the chain.

"Y-yes," Red breathed.

" _I'm_  your new master," he barked.

"Yes, master," Red replied as his neck was given another little tug. He had never seen anything like this before in Blue. All the other times he was in skeleheat, he just wanted cuddles and romantic kisses.

 _He must be on his ninth heat,_  Red thought as Blue licked his collarbone. _I remember when I had mine..._

Every nine skeleheats, the monster will crave dominance and lust after its lover. Sans had gone to Boss not knowing what to do in his ninth heat, so Boss just let him dominate for once to relieve him. But this was a whole different concept.

Red's neck was given an even harder tug as Blue went from his collarbone to his mouth and gave him a rough kiss. The glow in both Sans' pants were growing brighter.

The blue skeleton started to trail kisses down the red one. He lifted up his shirt and licked up and down his ribs, being careful to get every single inch of them.

"Pl-please, Blue... d-don't make me beg..." He was panting again. "You're such a damn tease."

"Then let's get a little more... busy..." Blue smirked as he tugged down his own pants and threw them across the room to reveal a throbbing ecto-pussy. "Lick it." He got atop Red's face. He instantly started to stick his tongue in and out of the hole.

Blue moaned loudly, practically screaming Red's name.

Meanwhile in Red's pants, his ecto-dick was begging for attention.

"RED!" Blue moaned as he came. Red licked all of it up, being as sweet as sugar and continued to lap at it.

"Damn, Blue, you taste so damn good!"

"More, more!" he moaned as he felt a second climax coming. "Faster!" Red obeyed and soon found the sweet juice again, lapping at it.

Almost exhausted, Red asked, "Blue... can my turn come now?"

Blue had almost forgot about Red's desires. "Okay..." He got up and went over to Red's shorts. He ripped them off and threw them across the room beside his pants.

"Can you at least untie me first? You did all the work, why not let me do the rest?"

"Fine... But you have to prove it."

"I will, _master,_ " he replied as the belt around his wrists were loosened enough for him to slip his hands out. He laid Sans on the bed and started to bite his collarbone.

"Ngh! Red!"

"Shhh. I'll make you feel good," he whispered. He put his fully erect member into the other Sans' pussy without warning. He began thrusting in and out in a pattern.

"RED! AGH!" Blue was so loud; he was sure to wake up the entire Underground.

"BLUE! Yes, Blue!"

"Faster!" Blue screamed. The other skeleton picked up the pace. "I'm gonna—AGH!" Blue leaked out juices all over Red's ecto-dick, making it easier for him to slide in and out. It wasn't long before he came too, screaming Blue's name as he did so.

"Shit..." Red said as he collapsed next to Blue. "You're amazing."

"I love you, Red."

"I love you, too, Blue."

The skeletons cuddled closely to each other, not even bothering the huge mess that they had just made, and fell fast asleep to the sound of each other's breathing.

 

 

Author's Note:

Sue me, bishes.

I love this shipping even though people say it's disgusting.

Oh friggin' well.

Anyhow, hope you enjoyed the smut!

There's more where that came from!

 


	2. Steaming Hot Bones

Blue woke up next to Red. Both were sore from last night but didn't want to admit it.

"Wake up," the little skeleton said, nudging the other one who was still asleep. "Come on..." He nudged him a bit harder. When that failed, he got an idea. Blue leaned in and met Red face to face. Summoning an ecto-tongue, he embraced them both into a warm kiss.

Red's sockets shot open as he summoned an ecto-tongue of his own to kiss his lover back.

"Good, you're awake," Blue said as he pulled back.

"And you still taste wonderful," the other retorted, giving a cocky smile.

Blue blushed and got out of the bed, grunting. "Ugh! I'm a mess! I'm gonna go take a shower, okay?"

"I'll come with you," Red insisted.

"What?"

"I said I'll take a shower with you. I'm a mess too and Boss will have my head on a silver platter if I come back smelling like this and looking like a total mess."

"Fine."

Blue took off the remainder of his clothes until he was completely bare. The bigger skeleton took off his clothes and saw that his soul was brighter than usual.

"Great," he mumbled under his breath. "At a time like this, you wouldn't expect this to be happening.  _Just_  great." He had gotten turned on by Blue and was a bit embarrassed about it.

The other skeleton had already started the water. "Are you coming?" he called out.

"Yeah! I'm coming, honey!" He shuffled his feet into the bathroom. Blue was already in the shower so he decided to get in and stand behind him.

"Did you just call me 'honey' back there?" he asked.

"I-I'm sorry, I won't do it again."

"Nah, nah, it's fine. It's just, no one's ever called me that before and... I don't know... I just wasn't expecting it I guess." He shrugged his shoulders and got two rags, handing one behind him for Red to grab.

"Thanks," Red said as he took the rag and started to wipe his self off. Seeing Blue in front of him, no clothes and hot water pouring in between each bone was making Red's soul burn even more. Every single motion he made just wanted to make Red jump on him and pound him.

"Are you okay?"

"What? Uh, yeah... Just... thinking about something." Red snapped out of his trance and stepped in front of Blue to wash his self off. If he didn't see Blue, he wouldn't have to worry about getting any more aroused than he already was.

"Um... Red?" Blue asked as he tapped his shoulder.

"Yeah?"

"You have a... a  _thing_  between your legs there."

Red looked down and the only thing he said was: "Oh shit!" He looked at Blue. "I'm sorry, I—"

"It's fine, really."

The only thing he could do was nod.

"Hey... don't be sorry about it... I mean... I'm having an after-effect of my heat so... maybe we can, you know, have some fun with it?"

"I thought we were supposed to be getting clean, not getting even more dirty."

"So?"

"Jeez, what ever turned you into such a slut?"

"You." Blue grabbed Red's face and brought him in for a tender, soft kiss. Red ran his boney fingers along the other's spine. "Mmm, more, please..." he mused.

"You're such a slut," he said as his fingers traced along his ribs causing even more moans. "Yeah, I know you like that..."

"Stop t-teasing me a-and actually do something." He summoned an ecto-pussy and looked down at Red's erection that had formed.

"You want me to take you right now?" Red asked, a bit confused. They were supposed to be cleaning off and that only. "Shower heat-sex isn't my thing, you know."

"It's gonna be." Blue laid down on the tub floor and propped his self so that his knees were up. "Come on, don't be shy..."

The water poured down on Blue, making Red want him more. So sexy... "Whatever you say." He got down on his knees and adjusted his pelvis so that it lined up with the other skeleton's entrance.

Without even a single word, Red pounded into Blue. The water from the shower made it easier but only by the slightest.

"AGHHHHH! RED!" Blue screamed his name entirely too loud. 

"Shhhh. Damn, you're gonna wake up Papyrus if you haven't already." He began to pull out slowly before he pounded in again and again rhythmically. "Man, you're tight today."

"Ngh... Please... R-Red... Uh!" He kept thrusting while Blue dug his fingers into Red's hip bones. "I'm gonna... come..."

"M-Me too!" Fell went faster until he came inside of Blue.

"Ahh, RED!" Blue screamed as he also came, creating a purple mess of magic on the tub floor.

"So much for getting clean, am I right?"

"Shut up."

Red let out a small chuckle and got up, holding Blue's hand to help him up too. Red kissed him and finished wiping off. They both got out of the shower, steaming from the hot water and decently cleaned off.

Once they were both dressed, Red set off to go back home and make sure that Boss still had his cool.

"Hey," Blue said before he went out the door. "Just remember that I love you. And if he hurts you, I'll take care of you, no matter how bad it may be." He got on his tiptoes and clanked Red's forehead.

"Thanks, hon. I love you too."

With that, he set off to his work station in Underfell. It was going to be one hell of a long day, that was for sure.

 

 

Author's Note:

Welp, this took longer to write than I would like to admit.

Editing these things can be such a douche sometimes.

More of the story coming either tomorrow or the day after tomorrow!

Sorry for the long wait.

 


	3. Nothing More But Your Warmth

It was the normal routine. Go to the station, have Boss "teach him a lesson" because he was caught sleeping, go back to the house, and then cry his self to sleep.

He was in the corner of his little cold room. Knees to his ribs and shivering. "I wish B-B-Blue was here with m-me. He's always so warm and c-cuddly." Red hugged his knees tighter, recreating Blue's gentle touch.

Soon after, he fell asleep, but had a nightmare.

 

_Blue was standing there, looking much taller than Red himself._

_"I'm sorry," Red said._

_"Don't be. You're pathetic. A nobody. I don't know why I even do anything for you, you worthless piece of crap."_

_"Please... I—"_

_"Save it! Worthless things like you don't deserve to talk. You don't deserve to breathe. Don't deserve to have a life." All the colour drained from the world around him. Blue's sockets were pitch black._

_"No..."_

_"But I guess I shouldn't expect something—"_

_"No..."_

_"From—"_

_"Please!"_

_"Nothing!"_

_"Blue, please!" He began to sob uncontrollably. Red flames surrounded him._

_"Wake up!" a voice said from the abyss. "Wake up! Wake up! Wake—"_

 

"Up! Sans!" Papyrus was shaking him as hard as he could but no matter what he did, Sans wouldn't budge. He sat there, crying, as red flames surrounded him.

"AGHHHH!" The little skeleton screamed as the red flames grew brighter.

"SANS! ENOUGH!" Boss smacked his face and immediately, he stopped crying. 

"B-Boss? I-m sorry. D-D-Don't punish me, p-please!"

"I won't..." His eye began to glow a soft red as he held Sans in the warmth of his arms.

 

 

Author's Note:

I feel like a piece of shit because I gave you all such a short chapter.

But this is the last chapter so I'm totally aloud to do it.

BYEEEEE!

 


End file.
